Researchers at the Technion have developed a technology to measure the long-term effect of antibiotic combinations (cocktails).

These combinations are of concern to the scientific and medical community due to the fact that the use of single antibiotics often leads to the rapid development of bacterial resistance to antibiotics. The research published in Nature was led by Technion researchers Prof. Roi Kishoni from the Faculty of Biology and the postdoctoral student in his laboratory Dr. Victoria Lazar (currently a faculty member at the European Union Institute for Biological Research in Szeged, Hungary).  

The researchers discovered that in many cases, a combination of several antibiotics may actually reduce the effectiveness of the treatment in the long term, that is, lead to the fact that the effectiveness of the combination is inferior to that of each individual drug. However, they point to specific combinations that do prevent the formation of resistance and thus protect the patient over time from the attacking bacteria.  

The bacterium tested in the study is Staphylococcus aureus –  a particularly violent bacterium that has developed resistance to many strains of antibiotics. This bacterium is responsible for a significant part of the infection cases that occur in hospitals and in the community. The study was conducted both in cultures of this bacterium in the laboratory and in an animal model (the moth Galleria mellonella ).    

Antibiotics are a family of drugs that play a central role in modern medicine and save lives on a daily basis. The natural antibiotic substances, which developed during evolution in fungi and yeast, were discovered about a century ago in the research of Sir Alexander Fleming, Howard Florey and Ernest Chain, winners of the Nobel Prize in Medicine for 1945. In these hundred years, antibiotic treatment has saved hundreds of millions of people.

However, the success of antibiotic therapy has turned it into a double-edged sword. This is because the widespread use of antibiotic drugs leads to the evolutionary development of antibiotic-resistant bacteria . This trend raises a justified fear of a post-antibiotic era  –  a time when bacteria will no longer respond to antibiotic drugs and people will die, as in the past, from infections that are now considered mild and not dangerous. 

The laboratory of Prof. Roy Kishoni, one of the leading experts in the field of antibiotic resistance, develops methods that make it possible to estimate in advance the resistance of a given bacterium to a given antibiotic in the present and furthermore – to predict the level of resistance it is expected to develop in the future. In the current study, as mentioned, combination treatments were examined – a combination of different antibiotic drugs that prevent the formation of resistance.

The researchers note that the corona epidemic has increased the use of antibiotics, since although the corona virus itself ( SARS-CoV-2 )  is not affected by antibiotics due to being a virus and not a bacterium, the antibiotic treatment helps corona patients to avoid secondary bacterial infections. And so, with the expansion of antibiotic use, the evolution of resistant Staphylococcus aureus strains accelerated .  

In conclusion, the Technion researchers discovered that combinations of antibiotics may harm the effectiveness of the treatment and point to specific combinations that accelerate or inhibit the development of bacterial resistance. In doing so, they pave the way for more effective treatments and the curbing of the  ” resistance epidemic ”  that threatens humanity.